This disclosure relates to polycarbonate compositions, and in particular to transparent polycarbonate compositions, methods of manufacture, and articles formed therefrom.
Polycarbonates are useful in the manufacture of articles and components for a wide range of applications, from automotive parts to electronic appliances. Because of their broad use, particularly in electronic applications or visually oriented applications such as light covers, see-through protective coverings, lenses, and transparent films, it is desirable to provide polycarbonates with excellent weatherability, impact strength, and transparency. Presently available polycarbonate films, for example, offer a number of advantages over poly(ethylene terephthalate) (PET) films, including higher heat distortion temperature (HDT), higher scratch resistance, and better performance under stringent environmental conditions. High temperature polycarbonates (polycarbonates having a glass transition temperature (Tg) of greater than about 200° C.) are expected to provide even better performance, but tend to be immiscible with other polymers, including other polycarbonates. Immiscibility can degrade physical properties, lead to processing difficulties, and lower optical clarity.
There accordingly remains a need in the art for methods for increasing the miscibility of high temperature polycarbonates with other polycarbonates. There also remains a need in the art for compositions that contain high temperature polycarbonates, wherein the compositions have advantageous properties such as heat stability and optical clarity.